[YarinQuapi]

What

• Adds the CI workflow for API, web and mobile (existing commit on this branch).
• Adds an in-memory stale-while-revalidate cache for GET responses on web (api.ts) and mobile (api.dart). Pages seed their state from the cache via peek(path) and still refetch in the background.
• Wired into Today, Fasting, Week, Weight, Settings and Permissions on both platforms, plus the food edit form on web.

Why

Every page change started from empty state and showed a loading spinner until the request finished.

Notes for reviewers

• Cache is cleared on login, logout and 401 (web setStoredToken, mobile setToken) so users never see each other's data.
• Week is cached per ?on= value; mobile ignores a stale week response if the user has navigated on.
• Cache is memory-only (lost on reload/restart). After a mutation, other pages may show the old value briefly until their background refresh lands.
• Food search and recent foods are not cached.
• Verified: npm run build passes and flutter analyze shows only pre-existing style hints. Not exercised manually in a browser or simulator.

🤖 Generated with Claude Code